First of all, I'd like to say that SANE is a great project and thank you
very much for bringing it to life.

Now about my problem/question:

I have a Mustek 1200 SP flatbed scanner connected to an SCSI card here.
The scanning image quality is excellent at first glance, but holds
a slight offset between scanning chunks (two or three scanning lines
per chunk).

In addition, the optical unit slides back after each chunk, making
the process of scanning very slow with color images.

Is there any way to remove the picture offset or to simply stop the
optical unit after each chunk instead of stop and move it back a
little?